There is a plurality of different types of switching devices, such as electric circuit breakers, known from the prior art. A very common type of switching device includes a rotary handle for being operated. Such switching devices are also denominated as rotary handle operator switching devices or RHO-devices.
For safety reasons, common RHO-devices include safety features restricting the operation of the RHO-device to avoid accidents caused by an unauthorized operation of the switching device. For example, when the rotary handle of a circuit breaker is set in an OFF position, e.g. because of maintenance work at an electronic circuit, one has to make sure that the rotary handle is not moved to an ON position during the maintenance work, in order to avoid an electric shock for the maintenance worker. For this reason, common circuit breakers include a locking mechanism for locking the rotary handle at least in the OFF position.
Moreover, in order to avoid an unauthorized operation of an electronic switching device, some switching devices include a locking mechanism for locking the rotary handle at least in the ON position. Furthermore, another known safety feature disables locking the rotary handle in the OFF position or even prevents moving the rotary handle to the OFF position in the case of a short circuit, especially when the main contacts of the electronic switching device are welded together.